Heart Work Sheet- Enjoy This handout will have some gaps in it which you will need to fill. Pay attention or you may miss them.
The Heart
Heart Wall The Heart Wall is composed of three layers: • • • Label the diagram
The bulk of the muscle wall is composed of the ……………………………… ... The ………………………………….is responsible for the contraction and relaxation of the ventricles and atria (this will discuss these later). The outside of the myocardium is covered with a thin layer called the ……………………………….. This thin layer consists mostly of connective tissue and fat. The inner lining of the heart is called the ………………………………………
At the centre of the cardiovascular we have the heart. The heart is centred on the left hand side of the chest beneath the sternum. The heart is about the size of a clenched fist. Heart Facts The heart can be thought of as two separate ……………………… The right side receives …...................................... and the left pumps oxygenated blood round the body. The ……………………………………………… is a solid wall separating the left side of the heart from the right.
Try and label the heart diagram: Right Side
Left Side
NAME THE PART THAT CORRESPONDS WITH THE PREVIOUS PAGE. 1. 9. 2. 10. 3. 11. 4. 12. 5. 13. 6. 14. 7. 15. 8. 16. 17.
Part of Heart Pulmonary Artery
Function These are the upper chambers of the heart. They receive blood returning to the heart from either the body or the lungs. The right receives blood from the superior and inferior vena cava and the left receives blood from pulmonary veins.
Pulmonary Vein
These are the pumping chambers of the heart. They have thicker walls than the atria. The right ventricle pumps blood to the pulmonary circulation for the lungs and the left ventricle pumps blood to the systemic circulation for the body.
Aorta
The valve is one of four in the heart. It is situated between the left atrium and the left ventricle. It allows the blood to flow in one direction only; from the left atrium to the left ventricle.
Bicuspid Valve
This valve is situated between the right atrium and the right ventricle. It allows blood to flow from the right atrium to the right ventricle.
Ventricles
These are cord like tendons that connect the bicuspid and tricuspid valves from turning inside out and ensure the correct flow of blood through the heart.
Atria
Another of the four valves in the heart, this valve lies between the left ventricle and the aorta. It prevents backflow from the aorta into the left ventricle.
Chordae tendinae
This valve lies between the right ventricle and the pulmonary artery. It prevents backflow from the pulmonary artery.
Inferior and Superior Vena Cava
This is the main artery in your body. It originates in the left ventricle and carries oxygenated blood to your body tissues except the lungs.
Pulmonary Valve
These veins receive deoxygenated blood from the upper and lower body and empty blood into the right atrium.
Tricuspid Valve
This vein carries oxygenated blood from the lungs to the left atrium of the heart.
Aortic Valve
This artery carries deoxygenated blood from your heart back to your lungs. It is the only artery in the body to carry deoxygenated blood.
Blood Vessels When the heart contracts, blood flows through the body via a complex network of blood vessels. Around ……………………………. of blood vessels maintain circulation throughout the body. The structure of these vessels is determined by the function of the blood vessel. Summarize the blood vessels here: Arteries
Veins
Capillaries
Arterioles These have thinner walls than arteries. These vessels control blood distribution by changing their diameter. Venuoles These have thinner walls than arterioles. They collect blood leaving the arterioles and transport it to the veins. Activity Draw a flow diagram to show the order in which blood flows through the blood vessels. Start with arteries.
Blood vessels cont’d At times we need to increase and decrease the blood flow in our bodies. This tends to be to enable efficient blood supply to muscles during exercise. As muscles are using oxygen more quickly an increase blood flow is required. When exercising, blood flow to other body parts can be restricted to some tissues which don’t have such a great need for the oxygen i.e. to our digestive system
What is the difference between vasodilation and vasoconstriction? ……………………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………… Blood: Red blood cells From now on we must refer to these as ……………………………………… Approx 240 –270 million Erythrocytes in every drop of blood. Contain …………………………………. giving blood a red colour Oxygen is attracted to the Haemoglobin (HB) and flows around the body. White Blood Cells From Now on we must call these ……………………………………….. Transparent in colour Cells of the immune system Destroy bacteria and harmful living organisms. Remove Diseased and injured tissue. Platelets
Platelets or Thromocytes Fragments of cells. Prevent blood loss from a damaged blood vessel. Act as a clotting agent / plug to repair tissue damage. I.E. A scab = Oxidised platelets. Haemophilia = no platelets
Review Questions 1. 2. 3. 4. 5. 6. 7.
Which artery is the only artery to carry deoxygenated blood? What does vasodilation mean and why is it necessary? Why are capillaries only one cell thick? Why is the left ventricle thicker than the right ventricle? In which blood cell will we find haemoglobin? Which blood cell clots our blood? Describe two differences between an artery and a vein.
Heart Work Sheet Number 2 – Have Fun! • •
An adult human has between 4 to 6 litres of blood Functions:
•
Transport materials to and from the body cells. Such as………………………………………………………………… Distributes heat in the body via…………………………………………..
• •
•
Provides defence against invading organisms. Which blood cells are responsible for this? …………………………………………………………………… Serves as a regulator in the body (homeostasis).
Which of the blood cell is responsible for the following? • • •
Transporting Oxygen? Clotting? Fighting Infection?
.......................................... .......................................... ……………………………………….
The Cardiac Cycle • • •
• • •
The heart has a natural pace maker called the ………….. …………….. …… ……….. You will often see this written as …………………. It is found in the upper region of the right atrium The sino atrial node sends electrical …………………….. that trigger each heart beat. The impulses spread through the ………………….prompting the cardiac muscle to contract in a coordinated manner. As the impulse spreads it reaches the ………. ………………………………… …… ……………… (AVN). This is situated in the lower section of the ………………… ……………………… ….. This in turn sends impulses to the ventricles causing them to contract.
Can you name the following parts? 1 2 3 4 5
The Bundle of His and the Purkinje fibres are the route that the electrical impulse follows in order to make the muscle contract. They are nerve fibres. Question Why does the electrical impulse travel to the bottom of the ventricles first and then spread upwards??? ……………………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………………………… The Cardiac Cycle What is it called when the heart is contracting? …………………………………….. What is it called when the heart is relaxing? ………………………………………….
Write a definition of Cardiac Cycle
The Three Phases of The Cardiac Cycle : summarize the cardiac cycle in the table below. Atrial Systole
Ventricular Systole
Diastole
0.8 seconds to complete one cardiac cycle.
Respiratory Worksheet- another one of those worksheets you enjoy so much…Have Fun!!!! The respiratory system: Also known as …………………….. or ……………………………… system Responsible for the provision of …………. and removal of………………, water vapour and heat Works in conjunction with the ………………………………………….. system
10 facts you already know about the respiratory system: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
Have a go at labelling this diagram: see how much you can get labelled in five minutes.
Upper respiratory tract: • Nose (2 nostrils and a nasal cavity) • Mouth • Pharynx • Larynx • These structures ………………….., ………………………. and …………………… inspired air Lower respiratory tract: Trachea (windpipe) Bronchi (left and right bronchus) Lungs: Bronchioles Alveoli These structures transport the filtered, moistened and warmed air to the lungs for …………………………. ………………… to take place
Review Questions 1. 2. 3. 4. 5. 6.
Why is air warmed as it enters the nose? What is the purpose of moistening the air? Why is the trachea made of cartilage? What is the purpose of the epiglottis? What is the main site of gas exchange in humans? What is the function of stretch receptors and where are they found? 7. Describe the role of stretch receptors (where are they found and what do they detect?) 8. How might you work out your breathing rate? 9. Why do we breathe more quickly and deeply when we exercise? 10. Give two differences between inhaled air and exhaled air. 11. What effect would a puncture through to the lungs have on breathing? 12. What is the golden rule in terms of air and pressure. 13. What is the difference between active and passive breathing? 14. What is tidal volume?
Complete the table which details how humans breathe in and out.
Gas Exchange
Capillary from pulmonary artery
Red cell
Oxygen enters red cells
Film of moisture
Epithelium of alveolus
To pulmonary vein
D iff us io n di of ox ca id e rb on
Carbon dioxide escapes into alveolus
Respiratory Volumes Respiratory rate How many times we breath in one …………………….. Tidal volume
…………….. of air breathed in and out with each breath
Expiratory reserve volume
Maximum additional volume which can be ……………… …… after normal tidal inspiration.
Inspiratory reserve volume
Maximum additional volume which can be ……………… ……… after normal tidal inspiration
Total lung capacity
Volume of air in the lungs after ………………….. inspiration
Residual volume
Amount of air left in the lungs after maximal ……… …………………………………..
Vital capacity
Maximal volume of air that can be …………………………… ………expired after maximal inspiration in one ………… …………………………..
Measurements of Lung Volumes by Spirometry
Control of Ventilation Neural
Chemical
The respiratory centre that controls the breathing rate is a part of the brain called the ………… ………. When we are breathing at rest impulses are sent to the ……………… ………………. causing it to contract at regular intervals. When we breathe the bronchi stretches, this stimulates the …… …………………………. receptors. These then send impulses to the medulla which in turn sends impulses to the diaphragm and intercostal muscles cause them to stop. The nerve that connects the stretch receptor is known as the vagus nerve.
……………………………… are found in the medulla, aorta and corotid artery. They are sensitive to changes in the ……………………… ……………….level. If the carbon dioxide levels increase the chemoreceptors are stimulated. They transmit impulses along …………. nerves to the diaphragm and intercostal muscles. This causes them to …………….. more frequently. When carbon dioxide levels are … ……………… the chemoreceptors are no longer stimulated.
Write down 4 new facts about the respiratory system you have learned: 1. 2. 3. 4. P H A R Y N X A S X Z C V G
S R O T P E C E R O M E H C
E T F S C B M B X M G K J L
R W R T H G F D U I O N P L
I H V B N M A S A E H F U T
P R F D E S E H J R K O P L
S G H J L O H P O I W D C V
N K Y H F E C W S P R T G B
I L O E V L A H G X G D E S
F L P O U Y R E S E R V E G
R E L A D I T H O R A X Q A
K U Y G P I O I K Y H D D S
L L A T S O C R E T N I K O
Pharynx Trachea Alveoli Reserve Tidal Chemoreceptors Inspire
Lung Expire Thorax Intercostal